Communication devices, such as mobile phones, may include an audio capture device, such as a microphone or speech synthesizer, an audio encoder to generate audio packets (or frames), a video capture device, such as a camera, and a video encoder to generate video frames. The communication device may use communication protocol layers, such as real-time transport protocol (RTP), radio link protocol (RLP), medium access control (MAC), and physical (PHY) layers. In a video telephony application, the communication device may place video and audio RTP packets in a RLP queue. A MAC layer module may generate MAC layer packets from contents of the RLP queue. The MAC layer packets may be converted to PHY layer packets for transmission across a communication channel to another communication device.